Behcet's (beh-CHETS) disease, also called Behcet's syndrome, is a rare disorder that causes inflammation in blood vessels throughout your body. The inflammation of Behcet's disease leads to numerous symptoms that may initially seem unrelated. The signs and symptoms of Behcet's disease — which may include mouth sores, eye inflammation, skin rashes and lesions, and genital sores — vary from person to person and may come and go on their own.

The exact cause of Behcet's is unknown, but it may be an autoimmune disorder, which means the body's immune system mistakenly attacks some of its own healthy cells. Both genetic and environmental factors may be responsible for Behcet's disease.

Treatment aims to reduce the signs and symptoms of Behcet's disease and to prevent serious complications, such as blindness.

Behcet's disease symptoms vary from person to person. Behcet's disease may disappear and recur on its own. The signs and symptoms that you may experience depend on which parts of your body are affected by the inflammation of Behcet's disease. Areas commonly affected by Behcet's disease include:

Mouth. Painful mouth sores, that look similar to canker sores, are the most common sign of Behcet's disease. Sores begin as raised, round lesions in the mouth that quickly turn into painful ulcers. The sores heal usually in about one to three weeks, though they do recur.

Skin. Skin lesions may occur in people with Behcet's disease. Skin problems can vary. Some people may develop acne-like sores on their bodies. Others may develop red, raised and tender nodules on their skin, especially on the lower legs.

Genitals. People with Behcet's disease may develop sores on their genitals. The sores commonly occur on the scrotum or the vulva. Sores appear as red, ulcerated lesions. The genital sores are usually painful and may leave scars.

Eyes. Behcet's disease may cause inflammation in the eye — a condition called uveitis (u-vee-I-tis). In people with Behcet's disease, uveitis causes redness, pain and blurred vision in one or both eyes and may come and go. Inflammation that occurs in the blood vessels of the retina is a serious complication of the disorder.

Joints. Joint swelling and pain often affect the knees in people with Behcet's disease. The ankles, elbows or wrists also may be involved. Signs and symptoms may last one to three weeks and go away on their own.

Vascular system. Inflammation in veins and large arteries may occur in Behcet's disease, causing redness, pain and swelling in the arms or legs when a blood clot results. In fact, many of the signs and symptoms of Behcet's are believed to be caused by inflammation of the blood vessels (vasculitis). Inflammation in the large arteries can lead to complications, such as aneurysms and narrowing or blockage of the vessel.

Digestive system. Behcet's disease may cause a variety of signs and symptoms that affect the digestive system, including abdominal pain, diarrhea or bleeding.

Brain. Behcet's disease may cause inflammation in the brain and nervous system that leads to headache, fever, disorientation, poor balance or stroke.

When to see a doctor

Make an appointment with your doctor if you notice any unusual signs and symptoms that might indicate Behcet's disease. If you've been diagnosed with Behcet's disease, see your doctor if you notice any new signs and symptoms.

Doctors don't know what causes Behcet's disease. However, a combination of genetic and environmental factors likely plays a role. Several genes have been found to be associated with the disease. Some researchers believe a virus or bacterium may trigger Behcet's disease in people who have certain genes that make them susceptible to Behcet's.

Factors that may increase your risk of Behcet's include:

Age. Behcet's disease commonly affects men and women in their 20s and 30s, though children and older adults also can develop the condition.

Location. Although the disease occurs worldwide, people from countries in the Middle East and Far East, including Turkey, Iran, Japan and China, are more likely to develop Behcet's.

Sex. While Behcet's disease occurs in both men and women, the disease is usually more severe in men.

Genes. Having certain genes is associated with a higher risk of developing Behcet's.

Behcet's disease typically comes and goes in unpredictable cycles. Symptoms may become less severe over time.

Though treatment can't cure Behcet's disease, it often can control signs and symptoms and reduce the risk of complications. For instance, untreated uveitis can lead to decreased vision or even blindness. People with eye signs and symptoms of Behcet's disease should be carefully monitored by an eye doctor because treatment can help prevent this complication. Other complications of Behcet's disease depend on the specific set of signs and symptoms you're experiencing.

You're likely to start by seeing your primary care doctor if you have signs and symptoms of Behcet's disease. But, because Behcet's disease is rare, and some of the signs and symptoms are similar to those of other disorders, you may need to see a specialist, such as a doctor who treats arthritis and other rheumatic illnesses (rheumatologist), before getting the diagnosis of Behcet's disease.

If a rheumatologist wasn't involved in your diagnosis, you may be referred to a rheumatologist for the management of Behcet's. Depending on your signs and symptoms, you may also need to see an eye doctor (ophthalmologist) for eye problems, a gynecologist or a urologist for genital sores, a dermatologist for skin problems, a gastroenterologist for digestive difficulties, or a neurologist for symptoms that involve the brain or central nervous system.

Because appointments can be brief and there's often a lot of ground to cover, it's a good idea to be prepared. Here's some information to help you get ready, and what to expect from your doctor.

What you can do

Write down any symptoms you're experiencing, including any that may seem unrelated to the reason for which you scheduled the appointment. Also, write down key personal information, including any major stresses or recent life changes.

Make a list of all medications, vitamins and supplements that you're taking.

If possible, bring a family member or friend with you. Sometimes it can be difficult to absorb all the information provided during an appointment. Someone who accompanies you may remember something that you missed or forgot.

Write down questions to ask your doctor.

Your time with your doctor is limited, so preparing a list of questions can help you make the most of your visit. List your questions from most important to least important in case time runs out. For Behcet's, some basic questions to ask your doctor include:

What do you think is causing my symptoms?

Are there any other possible causes for my symptoms?

Do I need any special tests?

Is this condition temporary?

What treatments are available? Which do you recommend?

I have another health condition. How can I best manage these conditions together?

Are there any brochures or other printed material that I can take with me? What websites or organizations do you recommend for gathering more information?

In addition to the questions that you've prepared, don't hesitate to ask additional questions during your appointment.

What to expect from your doctor

Your doctor is likely to ask you a number of questions. Being ready to answer them may reserve time to discuss points you want to spend more time on. Your doctor may ask:

What types of signs and symptoms have you been having?

How severe are your symptoms?

When did you begin experiencing symptoms?

Do you have symptoms all the time, or do they come and go?

Does anything seem to improve your symptoms?

What, if anything, appears to worsen your symptoms?

Is there anyone in your family who has a similar illness?

No tests can determine definitively whether or not you have Behcet's disease. Instead, your doctor relies primarily on your signs and symptoms to diagnose Behcet's disease. Your doctor may conduct blood tests or other laboratory tests to rule out other diseases and conditions.

Criteria have been established for the diagnosis of Behcet's disease, but these aren't always essential for the diagnosis of the disease. Your doctor may use other factors for your diagnosis. The classification criteria require:

Mouth sores. Because nearly everyone with Behcet's will have mouth sores at some point, this sign is generally necessary for a diagnosis. The diagnostic criteria require mouth sores that have recurred at least three times in 12 months.

In addition, you must have at least two additional signs, such as:

Genital sores. Sores that recur may indicate Behcet's disease.

Eye problems. An ophthalmologist can identify signs of inflammation in your eyes.

Skin sores. A variety of rashes or acne-like sores may be caused by Behcet's disease.

Positive pathergy test. In a pathergy test, your doctor inserts a sterile needle into your skin and then examines the area one to two days later. If the pathergy test is positive, a small red bump forms under your skin where the needle was inserted. This indicates your immune system is overreacting to a minor injury.

No cure exists for Behcet's disease. If your signs and symptoms of Behcet's disease are mild, your doctor may offer medications to control temporary flares in pain and inflammation. You may not need to take medication between flares. But if your signs and symptoms are more severe, your doctor may advise medications to control the signs and symptoms of Behcet's disease throughout your body, in addition to medications for the temporary flares. Several factors, including your age and sex, may influence the specific treatment your doctor recommends.

Treatments for individual signs and symptoms of Behcet's disease

Behcet's disease may come and go on its own in periods of flares and remissions. Your doctor works to control any signs and symptoms you experience during flares with medications such as:

Skin creams, gels and ointments. Topical medicines are applied directly to skin and genital sores in order to reduce inflammation and pain. These types of medications usually contain a corticosteroid drug that reduces inflammation or an anesthetic to relieve pain.

Mouth rinses. Special mouthwashes that contain corticosteroids and other agents to reduce the pain of mouth sores may ease your discomfort.

Eyedrops. Eyedrops containing corticosteroids or other anti-inflammatory medicines can relieve pain and redness in your eyes if inflammation is mild.

Systemic treatments for Behcet's disease

If topical medications don't help control skin rashes, or oral or genital ulcers, a medication called colchicine (Colcrys) is often recommended. Arthritis symptoms also may improve with colchicine.

Severe cases of Behcet's disease require treatments to control damage from the disease between flares. If you have moderate to severe Behcet's disease, your doctor may prescribe:

Corticosteroids to control inflammation. Corticosteroids, such as prednisone, in combination with other medications may reduce the inflammation caused by Behcet's disease. The signs and symptoms of Behcet's disease tend to recur when corticosteroids are used alone, so doctors often prescribe them with another medication to suppress the activity of your immune system (immunosuppressives). Side effects of corticosteroids include weight gain, persistent heartburn, high blood pressure and bone thinning (osteoporosis).

Medications that suppress your immune system. Immunosuppressive drugs suppress your immune system, which overreacts in Behcet's disease. By stopping your immune system from attacking normal, healthy tissues in your body, immunosuppressive drugs reduce the inflammation that your immune system causes. Immunosuppressive drugs that may play a role in controlling Behcet's disease include azathioprine (Imuran, Azasan), cyclosporine (Gengraf, Neoral, Sandimmune) and cyclophosphamide (Cytoxan). Since these medications suppress the actions of your immune system, they may increase your risk of infection. Other possible side effects include liver and kidney problems, low blood counts, and high blood pressure.

Medications that alter your immune system's response. Interferon alfa-2b (Intron A) regulates the activity of your immune system to control inflammation. It may help control skin sores, joint pain and eye inflammation in people with Behcet's disease. Side effects include flu-like signs and symptoms, such as muscle pain and fatigue. Interferon alfa-2b may be combined with other medications.

Medications that block a substance called tumor necrosis factor (TNF), such as infliximab (Remicade) and etanercept (Enbrel), are effective in treating some of the manifestations of Behcet's, especially for people who have more-severe or resistant symptoms. Side effects may include headache, skin rash and an increased risk of upper respiratory infections.

Other drugs that have been used to treat Behcet's disease include thalidomide (Thalomid), mycophenolate mofetil (CellCept) and chlorambucil (Leukeran).

The unpredictability of Behcet's disease can make it particularly frustrating. Taking good care of yourself may help you better cope with the ups and downs of Behcet's disease. Your approach to caring for yourself will depend on what signs and symptoms you're feeling on a particular day. In general, try to:

Rest during flares. When certain signs and symptoms such as mouth sores and joint pain appear, take time for yourself. Be flexible and adjust your schedule when possible so that you can rest when you need it. It's also a good idea to keep stress to a minimum, because stress can aggravate your symptoms.

Be active when you have the energy. Moderate exercise, such as walking or swimming, can make you feel better between Behcet's disease flares. Exercise strengthens your body, helps keep your joints flexible and can improve your mood.

Connect with others. Because Behcet's is a rare disorder, it may be difficult to find others with the disease nearby. However, ask your doctor about support groups in your area. If it's not possible to connect with someone close, the American Behcet's Disease Association offers message boards and chat rooms where you can connect with other people who have Behcet's.

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